Self-adjusting ship-mast



(No Model.)

J. MOLEOD. v Self Adjusting Ship Mast.

Patented Jan. 4,1881.

, G W A B N ETERS, PHDTO-LITHOGRAPNEI, WASMXNGTON.D. Cl

INVENTOR ATTORNEYS.

mw. M 4% UNITED STATES PATENT OFFICE.

JOHN MCLEOD, OF AUCKLAND NEW ZEALAND.

SELF-ADJUSTING SH l P-MAST.

SPECIFICATION forming part of Letters Patent No. 236,237, dated January4, 1881.

Application filed March 2, 1880.

To all whom it may concern:

Be it known that I, JOHN MGLEOD,OfA11Gklaud city, New Zealand, haveinvented a new and Improved Self-Adjusting Mast for Boats and Vessels,of which thelfollowing isa specification.

The object of this invention is to increase the safety and improve thesailing qualities of boats and vessels.

The invention consists of a mast hung so that it may swing from side toside on an axle ortrunnions on a thwart of a' boat or beams of a largervessel; and it consists, further, of a curved tube, preferably tubularand armed with strong springs fixed beneath the thwart or beams .for theheel of the mast to travel on,

said springs being preferably coiled about the curved tube and extendingfrom either side of the mast upward and outward, their upper ends beingrestrained by adjusting-nuts that are designed to compress and therebyincrease the tension of said springs; and it consists, further, of acounterbalance weight secured about the foot of the mast to increase theinertia thereof, and thereby co-operate with the said springs, and tooperate as self-adjusting ballast; and it consists, further, of springssecured to the shrouds to co-operate with the springs around the curvedtube to hold or restore the mast to its upright position.

Figure 1 is a transverse sectional elevation of a boat, showing theimproved device partly in section. Fig. 2 is a plan view, showing thethwart of a boat with the mast hu'ng or pivoted therein. Fig. 3 is apartly-sectional side elevation.

Similar letters of reference indicate corresponding parts.

In the drawing, A represents the hull of a boat. B is the thwart,provided with a central opening, a, about which is secured a metallicplate, I), provided with opposite verticallugs cc.

0 is the mast, that is set down through the (No model.)

or is in close contact with the curved tube E, which curved tube Eextends across the boathull A, its lower point being supported on theblock d, that is secured to the keelson F, while its arms extend upwardand outward through the said thwart B, near the ends thereof, as shown.The curved tube E consists, as shown, of a metal tube, having coiledabout each arm a spiral spring, f, that extends from the heel of themast O upward in contact with an adjusting screw-nut, 9, that is movableon said arm. On the ends of the curved tube E extending up through thethwart B are secured the sheaves h, and within the curved tube E aresecured the springs m.

The shrouds K, extending from the mast 0 down on either side thereof,enter the ends of the curved tube E, and are there made fast to the saidsprings m, the sheaves h, against which the shrouds K bear, serving torelieve their friction as the springs extend or retract. On the foot ofthe mast O is secured a block of metal, Gr, that serves as adjustableballast as the boat lies over, and as a counter-balance to hold the saidmast in an upright position and to assist in restoring the mast to suchposition after it has been moved from it.

With this device, in a boat or vessel under sail the mast will remain inits proper upright position under an ordinary wind, and the boat orvessel will list over as far as compatible with good sailing and safety;but under a heavy wind or squall the mast will yield to leeward andspill out of the sails all the wind or the pressure thereof that may bein excess of what the boat or vessel can carry, and on the slightestslacking of the wind the mast instantly begins to resume its primaryposition by reason of the windward springs fm and the counter-balance G,which counter-balance shifts to windward as the boat keels to leeward.Thus the speed of the boat or vessel maybe maintained without danger ofcapsizing.

Most accidents in open boats occur from the sheets 7 being belayed, sothat they cannot quickly be thrown off in a squall or sudden fresheningof the wind, or from jibbing when attempting to bring the boat closer tothe wind. Both'these causes of accidents may be avoided by the use ofthe device herein shown and described, as the boat or vessel would notlie over so that her keel would lose its hold upon the water, nor wouldthe boat or vessel make much leeway, but would always keep a goodsailing position.

In undecked or open boat-s the curved tube, springs, and counter-balancewould be put in shallow boxes in the spaces between the thwarts andkeelson. For yachts and other decked vessels the curved tube may beconstructed of a strong iron plate with flanges for the heel of the mastto move in while acting on the springs. The shrouds could be fastened tospring-chain plates, the plates being passed down through thecovering-boards inside the railing, or suitable springs could bearranged in any other part of the shrouds.

Having thus described my invention, I claim as new and desire to secureby Letters Patent The combination, with a boat havingcentrally-aperturcd thwart B, of the plate I), having lugs 0 c, thetrunnion D, the curved tube E, having inner and outer springs,fm, the

sheaves h, ropes K, and counter-balance Gr, all 2 arranged as and forthe purpose specified.

JOHN MOLEOD. Witnesses:

I. I. S'roRER, C. SEDGWICK.

